Keratinocytes switch between two modes of division in normal and wounded skin

February 12, 2016

Skin has two critical challenges. Maintaining the tissue requires that exactly the right number of new cells are generated to replace those shed from the skin surface. Making too many cells will generate a tumour, whereas too few will result in an ulcer.

Skin also has to heal rapidly after an injury. This requires a short burst of cell production to repair the damaged area.

It used to be thought that maintenance and repair required a rare population of skin stem cells. However, in a study published in Nature Cell Biology, Dr Amit Roshan and colleagues from Dr Phil Jones’ group (MRC Cancer Unit and Sanger Institute) analysed movies of thousands of divisions of cells grown from human skin.

The results showed that all dividing skin cells have the ability to sustain skin by dividing in ‘maintenance’ mode but can temporarily switch to ‘wound repair’ mode when required.

This result challenges the view that special skin stem cells are essential, explains the remarkable capacity of the skin to replace and regenerate itself throughout life, and will guide future research into wound healing and cancer.

As plastic surgeons, we have been growing sheets of skin from burns patients to save lives for decades.

A single skin cell can create a patch of one-centimetre diameter or more, and many of these together can make a whole sheet.

However until now we couldn’t explain how this worked. This research explains how skin cell cultures expand, and could lead to further improvements in wound healing in the clinic.